Electrical boxes for either new or old work are usually attached to supporting structures using two fasteners separated apart along a side. The usual method of attachment involves alignment of the electrical box with a frame post, such as a beam or sheet rock surface and then the attachment of one of the fasteners at least partially. Realignment and use of the second fastener follows. Boxes designed for new work typically have fastener bosses extending outward from the sides of the box precluding their use for old work where a sheet rock wall preexists the installation.
Among prior art patents, U.S. Pat. No. 6,093,890 of Gretz relates to a mounting device on an electrical or low voltage box which facilitates attachment to the underside of a sheet rock wall through an opening sized for the periphery of the box to permit use for new work.
U.S. Pat. No. 5,600,093 of Herth and Davis and U.S. Pat. No. 6,943,295 of Herth describe dual purpose electrical or low voltage boxes using interior mounting brackets guiding a fastener at an angle to exit the box wall for attachment to a beam. These boxes are equally useful for new or old work since the attachment is to a frame post, such as a wall stud or beam.
None of the prior art boxes are equipped with anti-rotation and alignment features which permit the efficient attachment to a frame post, such as a beam or stud, with a single fastener.